Systemic therapy for HER2+ Advanced Breast Cancer

Transcription

1 Systemic therapy for HER2+ Advanced Breast Cancer F. Cardoso, MD Director, Breast Unit, Champalimaud Clinical Center, Lisbon, Portugal ESMO Board of Directors & NR Committee Chair ESO Breast Cancer Program Coordinator EORTC Breast Group Chair

2 DISCLOSURES Consultant/Ad Board: Astellas/Medivation, AstraZeneca, Celgene, Daiichi-Sankyo, Eisai, GE Oncology, Genentech, GlaxoSmithKline, Macrogenics, Merck- Sharp, Merus BV, Novartis, Pfizer, Pierre-Fabre, Roche, Sanofi, Teva

3 MANAGEMENT OF HER-2 + MBC: ABC: primary or metastatic HER-2 status? Pivotal trials Combinations with CT and ET: when & which agents? Continue HER-2 blockade beyond progression (change of paradigm) Which anti-her-2 agent? Dual blockade? Best sequence of therapies? Overall good safety profile of anti-her-2 therapies but cardiac surveillance & management guidelines needed Important problem of brain metastases

4 HER-2 POSITIVE MBC Anti-HER-2 therapy should be offered early to all HER-2+ MetaBC patients, except in the presence of contra-indications for use of such therapy (LoE: 1 A). (91%)

5

6 Longer OS: 25.1 vs ms (p=0.046) Longer TTP: 7.4 vs. 4.6 ms (p<0.001) Higher RR: 50 vs. 32% (p<0.001) Longer duration: 9.1 vs. 6.1 ms (p<0.001)

7

8 IMPORTANCE OF STARTING ANTI-HER-2 AGENT EARLY ON

9 ER + / HER-2+ MBC For highly selected patients* with ER+/HER-2+ MBC, for whom ET is chosen over CT, ET should be given in combination with anti-her-2 therapy (either trastuzumab or lapatinib) since the combination provides PFS benefit (i.e. time without CT ) compared to ET alone. (LoE: 1 A) (72%) The addition of anti-her-2 therapy to ET in the 1 st line setting has not led to a survival benefit but long-term follow was not collected in the available trials. In addition, this strategy is currently being directly compared with CT + anti-her2 therapy. * Will be defined in the manuscript

10

11 IMPORTANCE OF STARTING ANTI-HER-2 AGENT EARLY ON

12 ER + / HER-2+ MBC For patients with ER+/HER-2+ MBC, for whom CT + anti-her2 therapy was chosen as 1 st line therapy and provided a benefit, it is reasonable to use ET + anti-her2 therapy as maintenance therapy, after stopping CT, although this strategy has not been studied. (LoE: 1 C) (80%)

13 HER-2 POSITIVE MBC MAIN MESSAGES: All patients with HER-2+ MBC who relapse after adjuvant anti-her-2 therapy should be considered for further anti-her-2 therapy, except in the presence of contraindications (LoE: 1 B) (97%) CHANGE IN PARADIGM IN ONCOLOGY!

14 Trastuzumab Beyond Trastuzumab: GBG-26 Study MBC HER2-positive Progression under trastuzumab-based first-line therapy (TFI < 6 weeks) with taxane (n = 114) or monotherapy or nontaxane (n = 42) R Capecitabine 2500 mg/m 2 bid d1-14 q21 days + continuation of trastuzumab 6 mg/kg q3 weeks (n = 78) Capecitabine 2500 mg/m 2 bid d1-14 q21 days (n = 78) R, randomization; TFI, treatment-free interval; MBD, metastatic breast cancer Von Minckwitz G, et al. J Clin Oncol. 2009;27(12):

15 Continuation of Trastuzumab Prolongs Time to Progression by Nearly 3 Months PFS Probability * Time from 1st progression, months * Trastuzumab + Capecitabine (n = 78) Capecitabine (n = 78) HR = 0.69 (two-sided P =.0338; one-sided P =.0169) Von Minckwitz G, et al. J Clin Oncol. 2009;27(12): *Median TTP in months TTP, time to progression; HR hazard ratio

16 HER-2 POSITIVE MBC In patients achieving a complete remission, the optimal duration of maintenance anti-her2 therapy is unknown and needs to be balanced against treatment toxicity, logistical burden and cost. Stopping anti-her2 therapy, after several years of sustained complete remission, may be considered in some patients, particularly if treatment re-challenge is available in case of progression. (LoE: Expert Opinion) (93%)

17 HER-2 POSITIVE MBC In the 1 st line setting, for HER-2+ MBC previously treated (in the adjuvant setting) or untreated with trastuzumab, combinations of CT + trastuzumab are superior to combinations of CT + lapatinib in terms of PFS and OS. (LoE: 1 A) (85%)

18 Gelmon, K. ASCO 2012 MA.31/ EGF COMPLETE TRIAL

19 MA.31/ EGF COMPLETE TRIAL Treatment Discontinuations OFF PROTOCOL TREATMENT (n = 382) LTAX/L=202 TTAX/T=180 Reason Number (%) Number (%) Death 5 (2.5) 10 (5.6) Intercurrent Illness 3 (1.5) 3 (1.7) Progressive Disease 143 (70.8) 121 (67.2) Toxicity 36 (17.8) 19 (10.6) Refused Treatment 2 (1.0) 4 (2.2) Symptomatic Progression 4 (2.0) 3 (1.7) Other 9 (4.5) 20 (11.1) Gelmon, K. ASCO 2012

20 NEW QUESTION: The optimal timing to use lapatinib? CEREBEL trial MA 31 Trial HR: 1.70 ( ) X ALTTO Trial ADAPTED FROM JAVIER CORTES

21 EGF104900: Phase III Study Evaluated Dual HER2 Blockade HER2 (FISH+/IHC3+) metastatic breast cancer Progression on Anthracycline Taxane Trastuzumab Progression on most recent trastuzumab regimen R A N D O M IZ E Lapatinib 1500 mg/d PO (n = 148) Crossover allowed to lapatinib + trastuzumab if progression after at least 4 weeks on therapy Primary endpoint: Progression-free survival Secondary endpoints: Overall survival Overall response rate Clinical benefit rate Lapatinib 1000 mg/d PO + trastuzumab 4 2 mg/kg IV weekly (n = 148) Staging occurred at 4, 8, 12, 16 weeks, and then every 8 weeks Steady state of single-agent lapatinib occurs at approximately 7 days Blackwell KL, J Clin Oncol 2010;28(7): Blackwell KL, et al. Cancer Res. 2009;69(24 Suppl): Abstract 61.

22 EGF104900: Significant Overall Survival (OS) Benefit With Trastuzumab + Lapatinib Following Disease Progression % L N = 148 L+T N = 148 Died, N (%) 113 (78) 105 (72) Survival, % % 6 Month OS 56% 41% Median, months Hazard ratio (95% CI).74 ( ) Log-rank P-value Month OS Patients at risk: Time from Randomization, months L L+T Blackwell KL, et al. Cancer Res. 2009;69(Suppl 2): Abstract 61.

23 Trastuzumab and Pertuzumab Bind to Different Regions on HER2 and Have Synergistic Activity Trastuzumab HER2 receptor Pertuzumab Dimerisation domain of HER2 Subdomain IV of HER2 Trastuzumab suppresses HER2 activity Flags cells for destruction by the immune system Pertuzumab inhibits HER2 heterodimerization THE CONCEPT OF DUAL BLOCKADE Suppresses multiple HER signaling pathways Flags cells for destruction by the immune system

24 CLEOPATRA TRIAL: Phase III, Randomized, Double-Blind, Placebo- Controlled; Placebo + Trastuzumab + Docetaxel vs. Pertuzumab + Trastuzumab + Docetaxel in Patients with Previously Untreated HER-2+ MBC n=406 Placebo + trastuzumab PD Patients with HER2-positive MBC centrally confirmed (N = 808) 1:1 Docetaxel* 6 cycles recommended Pertuzumab + trastuzumab PD n=402 Docetaxel* 6 cycles recommended PRIMARY ENDPOINT: PFS Randomization was stratified by geographic region and prior treatment status (neo/adjuvant chemotherapy received or not) *<6 cycles allowed for unacceptable toxicity or PD; >6 cycles allowed at investigator discretion Baselga, J. SABCS 2011

25 CLEOPATRA TRIAL: Median PFS and OS CAUTION!!!! Only 21% -26% pts had previously received (neo)adjuvant trastuzumab Progression-free Survival (%) HR=0.62 p< Ptz+T+D: 18.5 mo. Pla+T+D: 12.4 mo. =6.1 mo Time (months) Overall Survival (%) HR 0.68 p = Ptz+T+D: 56.5 mo. Pla+T+D: 40.8 mo. =15.7 mo Time (months) Baselga et al., NEJM 2012., Swain et al., NEJM, 2015.

26 Overall survival subgroup analyses An exploratory subgroup analysis was performed for patients who had received prior neoadjuvant and/or adjuvant trastuzumab therapy (88 patients). The observed hazard ratio of 0.68 (95% CI ) indicates overall survival benefit in the pertuzumab arm for this subpopulation.

27 Adverse events (all grades) with 25% incidence or 5% difference between arms n (%) Placebo + trastuzumab + docetaxel (n=396) Pertuzumab + trastuzumab + docetaxel (n=408) Diarrhea 191 (48.2) 278 (68.1) Alopecia 240 (60.6) 248 (60.8) Neutropenia 197 (49.7) 216 (52.9) Nausea 168 (42.4) 179 (43.9) Fatigue 148 (37.4) 155 (38.0) Rash 95(24.0) 149 (36.5) Decreased appetite 105 (26.5) 121(29.7) Mucosal inflammation 79 (19.9) 112 (27.5) Asthenia 121 (30.6) 110 (27.0) Vomiting 97 (24.5) 104 (25.5) Peripheral edema 122 (30.8) 101 (24.8) Pruritus 40 (10.1) 68 (16.7) Constipation 101 (25.5) 63 (15.4) Febrile neutropenia 30 (7.6) 56 (13.7) Dry skin 23 (5.8) 44 (10.8) Highlighted are adverse events with 5% higher incidence No increase in cardiac toxicity!

28 Phase II Study of Pertuzumab, Trastuzumab, and Weekly Paclitaxel 36 evaluable pts with 1 st or 2 nd line HER2+ MBC ORR = 47% No cardiac events Datko F et al, SABCS Abstract P

29 Safety of pertuzumab plus trastuzumab plus vinorelbine for 1 st line treatment of pts with HER2-+ LABC or MBC Edith A. Perez, José Manuel López-Vega, Lucia Del Mastro, Thierry Petit, Claudio Zamagni, Ulrich Freudensprung, Lydie Bastière-Truchot, Ru Walker, Michael Andersson. SABCS 2013, Poster

30 1 st Line Phase III MARIANNE Study Patients with HER2 positive progressive or recurrent locally advanced breast cancer or previously untreated metastatic breast cancer n=1092 Patients stratified by: World region Neo/Adjuvant therapy (Y/N) Trastuzumab + taxane DID NOT SHOW SUPERIORITY OF DUAL BLOCKADE! Visceral disease (Y/N) T-DM1 + pertuzumab Great Trastuzumab majority and/or of pts previously pretreated with Trastuzumab lapatinib based therapy in (Y/N) the (neo)adjuvant setting T-DM1 + placebo Primary endpoints: PFS as assessed by IRF; Safety Secondary endpoints: OS; PFS by investigator; PRO analyses; Biomarkers Superiority design with a Non-inferiority analysis between each of the experimental arms and the control arm Interim futility analysis: Option to drop experimental arm

31

32

33 T-DM1 treatment resulted in non-inferior but not superior PFS compared with trastuzumab plus a taxane in pts with locally advanced or metastatic HER2+ BC. The addition of pertuzumab to T-DM1 provided no efficacy benefit

34 PHEREXA study design NCT HER2-positive MBC (centrally confirmed) Prior taxane and H Progression during or after H-based therapy for MBC N = Arm A: H (8 mg/kg 6 mg/kg) + X (1,250 mg/m 2 ) n = 224 Arm B: H (8 mg/kg 6 mg/kg) + X (1,000 mg/m 2 ) + P (840 mg 420 mg) n = 228 First pt included: Jan 30, 2010 Last pt included: Aug 12, 2013 Clinical cut-off: May 29, 2015 Presented by Ander Urruticoechea

35 Primary analysis: PFS by independent review facility ITT population Proportion progression-free Arm A Arm B Time (months) a Stratified. CI, confidence interval; FU, follow-up. Arm A: H + X (n = 224) Arm B: H + X + P (n = 228) Events, n (%) 158 (71) 168 (74) mpfs (months) (months) 2.1 HR (95% CI) a 0.82 ( ) Log-rank p-value a 0.07 mfu (months) Presented by Ander Urruticoechea

36 Secondary analysis: OS ITT population a Stratified. Proportion surviving Arm A Arm B Arm A: H + X (n = 224) Arm B: H + X + P (n = 228) Events, n (%) 115 (51) 98 (43) mos (months) (months) 8.0 HR (95% CI) a 0.68 ( ) mfu (months) Time (months) Statistical significance cannot be claimed due to the hierarchical testing of OS after the primary IRF PFS endpoint Presented by Ander Urruticoechea

37 HER-2 POSITIVE MBC: 1 st line The standard 1 st line therapy for patients previously untreated with anti-her-2 therapy is the combination of CT + trastuzumab and pertuzumab, because it has proven to be superior to CT + trastuzumab in terms of OS in this population. (LoE: 1 A) (86%) For patients previously treated (in the (neo)adjuvant setting) with anti-her-2 therapy, the combination of CT + trastuzumab and pertuzumab is an important option for 1 st line therapy. (LoE: 1 A) (76%) Few (88) of these pts were treated in the Cleopatra trial and all with trastuzumab-free interval > 12 months.

38 HER-2 POSITIVE MBC There are currently no data supporting the use of dual blockade with trastuzumab + pertuzumab and CT beyond progression (i.e. continuing dual blockade beyond progression) and therefore this 3 drug regimen should not be given beyond progression outside clinical trials. (86%) There are no data on how to treat patients who have a relapse after receiving CT + trastuzumab + pertuzumab in the early setting.

39 HER-2 POSITIVE MBC In a HER-2+ MBC patient, previously untreated with the combination of CT + trastuzumab + pertuzumab, it is acceptable to use this treatment after 1 st line, although currently no data exists in this setting. (LoE: Expert Opinion) (76%)

40 HER-2 POSITIVE MBC After 1 st line trastuzumab-based therapy, T-DM1 provides superior efficacy relative to other HER-2-based therapies in the 2 nd line (vs. lapatinib + capecitabine) and beyond (vs. treatment of physician s choice). T-DM1 should be preferred in patients who have progressed through at least 1 line of trastuzumab-based therapy, because it provides an OS benefit. (LoE: 1 A) (88%) However, there are no data on the use of T-DM1 after dual blockade with trastuzumab + pertuzumab.

41 EMILIA Study Design HER2+ (central) LABC or MBC (N = 980) T-DM1 3.6 mg/kg q3w IV PD Prior taxane and trastuzumab Progression on metastatic tx or within 6 mos of adjuvant tx 1:1 Capecitabine 1000 mg/m 2 orally bid, days 1 14, q3w + Lapatinib 1250 mg/day orally qd PD Stratification factors: World region, number of prior chemo regimens for MBC or unresectable LABC, presence of visceral disease Primary end points: PFS by independent review, OS, and safety Key secondary end points: PFS by investigator, ORR, duration of response, time to symptom progression Blackwell K, et al. J Clin Oncol. 2012;30(15S): Abstract LBA1 & Vema S et al, ESMO 2012

42 EMILIA Study T-DM1 vs Cap+Lap ~5 MS BENEFIT IN OS Probably a new standard of care!

43 TH3RESA Study Schema HER2-positive (central) advanced BC a (N=600) 2 T-DM1 3.6 mg/kg q3w IV (n=400) PD 2 prior HER2-directed therapies for advanced BC Prior treatment with trastuzumab, lapatinib, and a taxane 1 Treatment of physician s choice (TPC) b (n=200) PD T-DM1 c (optional crossover) Stratification factors: World region, number of prior regimens for advanced BC, d presence of visceral disease Co-primary endpoints: PFS by investigator and OS Key secondary endpoints: ORR by investigator and safety a Advanced BC includes MBC and unresectable locally advanced/recurrent BC. b TPC could have been single-agent chemotherapy, hormonal therapy, or HER2-directed therapy, or a combination of a HER2-directed therapy with a chemotherapy, hormonal therapy, or other HER2-directed therapy. c First patient in: Sep Study amended Sep 2012 (following EMILIA 2nd interim OS results) to allow patients in the TPC arm to receive T-DM1 after documented PD. d Excluding single-agent hormonal therapy. BC, breast cancer; IV, intravenous; ORR, objective response rate; PD, progressive disease; q3w, every 3 weeks

44 SUPERIOR PFS SABCS % of TPC arm pts received T-DM1 crossover therapy 3 ms OS BENEFIT

45 COMMON TOXICITIES OF T-DM1 Thrombocytopenia Grade 3 in approximately 10% of patients Nadir on day 8; Nadir is typically lowest in cycle 1 Not typically cumulative Usually manageable with dose reduction Severe hemorrhage is rare, but small number of cases have been reported Transaminase elevation Grade 3 in approximately 5% of patients Not typically cumulative Usually manageable with dose reduction Severe hepatic dysfunction very rare Diéras et al, SABCS 2012, Abstract P

46 UNCOMMON TOXICITIES OF T-DM1 Pneumonitis( 1% of pts) Typically grade 1/2 T-DM1 should be discontinued Nodular regenerative hyperplasia (<0.5%) Can lead to noncirrhotic portal hypertension Requires biopsy to diagnose T-DM1 should be discontinued Diéras et al, SABCS 2012, Abstract P

47 HER-2 POSITIVE MBC In patients achieving a complete remission, the optimal duration of maintenance anti-her2 therapy is unknown and needs to be balanced against treatment toxicity, logistical burden and cost. Stopping anti-her2 therapy, after several years of sustained complete remission, may be considered in some patients, particularly if treatment re-challenge is available in case of progression. (LoE: Expert Opinion) (93%)

48 HER-2 POSITIVE MBC: CHEMOTHERAPY COMPONENT Regarding the CT component of HER-2 positive MBC treatment: When pertuzumab is not given, 1 st line regimens for HER-2 MBC can include trastuzumab combined with a vinorelbine or a taxane. (LoE: 1 A) (88%) Differences in toxicity between these regimens should be considered and discussed with the patient in making a final decision. Other CT agents can be administered with trastuzumab but are not as well studied and are not preferred. In manuscript: Single agent vinorelbine in association with anti-her-2 therapy has shown superior or equal efficacy compared to taxanes and has a better tolerability.

49 Extrapolating from HER-2+ disease: Vinorelbine seems at least as good as taxane and significantly less toxic TRAVIOTA: Taxane + Trastuzumab vs. Vinorelbine + Trastuzumab Vinorelbine & Capecitabine: Consistent efficacy results & NO ALOPECIA First-line MBC No prior trastuzumab Measurable Disease N=81 RR Paclitaxel or Docetaxel + Trastuzumab Vinorelbine + Trastuzumab TTP Taxane Arm 58% 6.0 months Vinorelbine Arm 66% 8.5 months p=0.09 Burstein HJ, et al. Cancer. 2007;110:

50 HER-2 POSITIVE MBC: CHEMOTHERAPY COMPONENT For later lines of therapy, trastuzumab can be administered with several CT agents, including but not limited to, vinorelbine (if not given in 1 st line), taxanes (if not given in 1 st line), capecitabine, eribulin, liposomal anthracyclines, platinum, gemcitabine, or metronomic CM. (LoE: 2 A) 891%) The decision should be individualized and take into account different toxicity profiles, previous exposure, patient preferences, and country availability.

51 HER-2 POSITIVE MBC: CHEMOTHERAPY COMPONENT CT agents to combine with a dual blockade of trastuzumab + pertuzumab are docetaxel (LoE: 1 A) or paclitaxel (LoE: 1 B). Also possible are vinorelbine (LoE: 2 A) and nab-paclitaxel (LoE: 2 B). (86% Consensus)

52 New anti-her agents

53 Margetuximab-Fc-optimized anti-her2 Monoclonal Ab Derived from 4D5, parent antibody of trastuzumab Margetuximab and trastuzumab bind same epitope on HER2 with high affinity Fc domain modifications enhance NK cell and macrophage activation Enhanced binding to low affinity variants of activating Fcγ receptor, CD16A Diminished binding to inhibitory Fcγ receptor, CD32B Enhanced antibody dependent cell-mediated cytotoxicity in vitro Patients with high affinity Fc receptors had prolonged PFS with trastuzumab (Musolino et al., J Clin Oncol 26: (2008)) SOPHIA will test if enhanced ADCC leads to superior outcomes in HER+ MBC Nordstrom JL, et al. Breast Cancer Research 13:R123,

54 SOPHIA Study to Establish Superiority to Trastuzumab Arm 1 margetuximab + chemotherapy HER2+ mbc, 1-2 lines in metastatic setting (prior trastuzumab, pertuzumab, T-DM1) PI Choice of Chemotherapy (capecitabine, eribulin, gemcitabine or vinorelbine) R 1:1 Randomization (n = 530) Arm 2 trastuzumab + chemotherapy Sequential Primary Endpoints: Progression-Free Survival & Overall Survival: PFS (N=257, HR=0.67, α=0.05, power=90%) OS (N=358, HR=0.75, α=0.05, power=80%) 54

55 Brain Metastases

56 Incidence of CNS Metastases in Trastuzumab-Treated Patients Case Series Patient Population # Overall % Bendell et al, 2003 Trastuzumab-treated Clayton et al, 2004 Trastuzumab-treated Lai et al, 2004 Trastuzumab-treated Lower et al, 2003 Trastuzumab-treated Non-trastuzumab-treated Pinder et al, 2007 Trastuzumab-treated first-line Non-trastuzumab-treated Shmueli et al, 2004 Trastuzumab-treated Stemmler et al, 2006 Trastuzumab-treated Yardley et al, 2007 HER2-positive MBC Yau et al, 2006 Trastuzumab-treated Leyland-Jones B. J Clin Oncol. 2009;27(31):

57 BRAIN METASTASES Patients with a single or a small number of potentially resectable brain metastasis should be treated with surgery or radiosurgery. Radiosurgery is also an option for some unresectable brain metastases. (LoE: 1 B) (92%) If surgery/radiosurgery is performed it may be followed by whole brain radiotherapy but this should be discussed in detail with the patient, balancing the longer duration of intracranial disease control and the risk of neurocognitive effects (LoE: 1 B) (72%) A multi-disciplinary discussion including neurosurgeons, radiation oncologists and medical oncologists is indispensable in determining the optimal treatment for each patient. The treatment plan can also be a combination of these three available therapeutic approaches

58 HER-2 POSITIVE MBC & BRAIN METASTASES Because patients with HER2+ve MBC and brain metastases can live for several years, consideration of long term toxicity is important and less toxic local therapy options (e.g. stereotactic RT) should be preferred to whole brain RT, when available and appropriate (e.g. in the setting of a limited number of brain metastases). (LoE: 1C) (89%)

59 HER-2 POSITIVE MBC & BRAIN METASTASES in patients with HER2 positive ABC who develop brain metastases with stable extracranial disease, systemic therapy should not be changed. (LoE: 1 C) (95%) For patients with HER2 positive cancers where brain metastases are the only site of recurrence, the addition of CT to local therapy is not known to alter the course of the disease. It is recommended to re-start the anti-her2 therapy (trastuzumab) if this had been stopped. (LoE: 1 C) (83%)

60 Trastuzumab Improves Survival in Patients With mcns Disease: U S Retrospective Analysis Survival (%) HER2 positive, trastuzumab (n = 36) HER2 positive, no trastuzumab (n = 11) HER2 negative (n = 48) P< Time from diagnosis of mcns disease (months) Kirsch DG, et al. J Clin Oncol. 2005;23(9):

61 LANDSCAPE STUDY: a FNCLCC phase II study with lapatinib and capecitabine in pts with brain metastases from HER-2+ MBC before whole brain RT 45 pts Primary endpoint: CNS volumetric response CNS-OR: 29/43 = 67.4% (95% CI: 52-81) CNS volumetric change N = 43 (%) 80% reduction 9 (20.9) 50-<80% reduction 20 (46.5) 20- <50% reduction 6 (14) > 0- <20% reduction 2 (4.7) Progression* 6 (14) * 2 patients had extra-cns disease progression NSS improvement: 14/24 = 58.3% (95% CI: ) IMP: pts previously untreated with WBRT; phase 2 study Bachelot et al, ASCO 2011

62 CEREBEL Study: A Phase III Randomized Open-Label Study of Lapatinib plus Capecitabine vs Trastuzumab + Capecitabine in HER2-Positive Metastatic Breast Cancer Inclusion Criteria: Stage IV HER2+ breast cancer Prior anthracycline and a taxane Prior treatment with CT, trastuzumab, HT, RT is permitted LVEF 50%, normal organ function Main Exclusion Criteria: History and/or current evidence of CNS metastases Prior therapy with lapatinib or ErbB2 inhibitor other than trastuzumab R A N D O M I Z E EARLY CLOSURE!! Capecitabine 2500 mg/m 2 bid d1-14 q21 days + Trastuzumab loading dose 8 mg/kg 6 mg/kg q3 weeks 475 pts enrolled 40% completed 12 months, had PD or died Lapatinib 1250 mg PO qd continuously + capecitabine 2000 mg/m 2 /d PO days 1-14 q3 weeks Primary endpoint: Incidence of CNS metastases at site of first relapse Secondary endpoints: Incidence of CNS progression at any time, time to first CNS progression, PFS, OS, ORR, CBR, duration of response, toxicity, pharmacogenetics, and biomarker analysis

63 Primary endpoint: CNS endpoints (modified ITT) Lapatinib + capecitabine (N=251) Trastuzumab + capecitabine (N=250) CNS as first site of relapse, n (%) 8 (3) 12 (5) Incidence of CNS progression at any time, n (%) Time to first CNS progression, median (range) 17 (7) 15 (6) OR (95% CI) 0.65 (0.26, 1.63) 1.14 (0.52, 2.51) p-value (2 17) 4.4 (2 27) - - LOW NUMBER OF BRAIN METS TRASTUZUMAB + CAPECITABINE BETTER

64 HER-2 POSITIVE MBC All patients with HER-2+ MBC who relapse after adjuvant anti- HER-2 therapy should be considered for further anti-her-2 therapy, except in the presence of contraindications (LoE: 1 B) (97%) The choice of the anti-her-2 agent will depend on countryspecific availability, the specific anti-her-2 therapy previously administered, and the relapse free interval. (88%) The optimal sequence of all available anti-her-2 therapies is currently unknown. (88%) The optimal duration of anti-her-2 therapy for MBC (i.e. when to stop these agents) is currently unknown. (97%)

65 MANAGEMENT OF HER-2 + MBC: MANY QUESTIONS SILL UNANSWERED Optimal duration of anti-her-2 therapy for ABC (indefinitely?) At progression should only the cytotoxic drug be changed of both the cytotoxic and the anti-her-2 agent Is treatment beyond PD also true for other anti-her-2 agents? Dual blockade for everyone or some? The role of the dual blockade without CT Triple blockade? Best sequence of anti-her-2 therapies Mechanisms of resistance & ways to overcome it; Predictive markers (role of PI3K mutations,...) NEW ANTI-HER-2 AGENTS in development

66